Flow Stop Prevention of Air Leakage at Ventilation Registers

ABSTRACT

A flow stop is formed of a sheet of impermeable material shaped as a bag having a closed end and an open end opposed to the closed end. The open end of the impermeable bag fits over the skirt (or diffuser) of a ventilation register and clamps about the skirt using an elastic band fixed about the open end. The flow stop bag has a noise suppressing elastic member secured across a portion of the closed end.

FIELD OF THE INVENTION

The present invention is directed to the field of heating ventilation and air conditioning using forced air. More particularly, the present invention is directed to control of airflow through a ventilation duct at a ventilation register.

BACKGROUND INFORMATION

Fully sealing off airflow through a ventilation register would save energy (heating or cooling) by securely preventing airflow through registers in rooms that are not being used, for example, an unused guest bedroom. Air that leaks from a nominally closed ventilation register represents wasted energy.

The damper function of typical residential ventilation registers is ineffective to completely block airflow, and fails to completely stop heating or cooling of unused spaces. Some commercial ventilation registers may have a damper function that can more fully block airflow, but these are expensive and are not economically viable as a popular choice to replace the typical cheap ventilation registers used in residential central air handling systems.

A number of proposals have been made for modifying or blocking airflow at a ventilation register. U.S. Pat. No. 4,520,715 to Coomes et al. discloses an apparatus that would cover room air registers. U.S. Pat. No. 5,213,543 to Clarino discloses an aircap cover assembly for ceiling registers. Published patent application US 2008/0160904 by Yi et al. discloses a vent cover function of paired male and female diffusers that combine to block airflow. U.S. Pat. No. 5,596,392 to Hawkins et al. discloses a register filter having an elastic band 34. U.S. Pat. No. 1,274,996 to Davis discloses a mechanically engaged removable cover for hot air flues. U.S. Pat. No. 5,479,984 to Easterbrook et al. discloses a magnetic affixed removable shut-off panel. U.S. Pat. No. 5,435,781 to Kitchens discloses a register with a functional mode to block airflow. U.S. Pat. No. 6,776,709 to Moore, Jr. et al. discloses a selectively closable floor vent cover.

The various vent covering or blocking schemes suffer from at least one of several disadvantages. Some are too expensive (as compared to estimated monetary savings from reduced energy waste) for homeowners to justify their widespread adoption. Some cannot be retrofit to an existing typical residential ventilation register, and would require replacement of the existing register. Some are impractical or simply unsightly.

What is needed is a practical energy saving measure to block flow of air through a residential ventilation register that does not cost so much as to offset the energy savings. Making energy savings economically advantageous (i.e., affordable) and practical, improves chances of adoption of such a measure by substantial numbers of people.

SUMMARY OF THE INVENTION

One aspect of the flow stop is a sheet of impermeable material shaped as a bag having a closed end and an open end opposed to the closed end, where the sheet has an elastic member fixed about the open end.

Another aspect of the flow stop is a sheet of impermeable material shaped as a bag having a closed end and an open end opposed to the closed end, where an elastic member is fixed across a portion of the closed end.

Yet another aspect of the flow stop is blockage of air using an impermeable sheet formed substantially of polymer material.

Still another aspect of the flow stop is blockage of airflow using an impermeable sheet comprising nonwoven fabric.

According to one embodiment, the flow control is for use in combination with a ventilation register having a faceplate with a vent and skirt extending outwardly from the face plate for insertion into a forced air duct outlet. The flow control is adapted for disposition about the skirt for blockage of airflow from the duct outlet. The flow control device has an impermeable and pliable sheet material, a clamp structure, and a noise suppression member. The clamp structure is secured along the periphery of the sheet material to secure the sheet material to the skirt. The noise suppression member is secured laterally across the sheet material to apply tension force to the sheet material.

The flow control is intended for use with a ventilation register and according to another embodiment has an air impermeable bag, a peripheral tension structure, and a motion control tension structure. The bag has a first, closed end and a second, open end. The peripheral tension structure includes an elastic band that is connected about a peripheral edge of the open end of the bag and is sized to provide a gripping fit of the open end about a portion of the ventilation register. The motion control tension structure is connected to the closed end of the bag to apply tension force across the sheet when the bag is fitted to the register and subject to fluid pressure when blocking airflow. The motion control tension structure includes at least one piece of elongated elastic material disposed across the closed end and having opposed ends attached at, or near to, the peripheral tension structure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a flow stop according to one embodiment.

FIG. 2 shows an exploded view of a flow stop according to FIG. 1, relative to a ventilation register (shown in phantom).

FIG. 3 shows a cross section view of the flow stop of FIG. 1.

FIG. 4 shows a detail view of ends of elastic strips of the flow stop according to FIG. 3.

FIG. 5 shows a detail view of ends of elastic strips of the flow stop according to an alternate embodiment.

FIG. 6 shows a perspective view of a flow stop according to another alternate embodiment.

DETAILED DESCRIPTION

Referring to FIG. 1, a first embodiment of the flow stop 100 is shown in perspective view. The flow stop 100 has a body 110 with four sides 112, 114, 116, 118, a closed bottom end 120, and an open top end, 122. An elastic band 130 is disposed around the top edges of the four sides 112, 114, 116, 118 that make up a peripheral edge 124 of the open top end 122. Elastic strips 140, 150 are each disposed across the closed bottom end 120 and two opposed sides 114, 118. The first ends 142, 152 of the elastic strips 140, 150 extend to, or near to, the elastic band 130 on one side 118, and the second ends 144, 154 (not shown in this view; refer to FIG. 5) extend to, or near to, the elastic band 130 on the opposed side 114.

The body 110 is shaped to have a generally bag-like form, albeit a shallow bag that is wider along at least one lateral dimension than it is deep. The elastic band 130 provides the spring force that holds the body 110 of the flow stop 100 in place on a ventilation register. The elastic strips 140, 150 apply tension force across the closed end 120. The tension force applied to the closed end 120 by the elastic strips 140, 150 serves to prevent any excess material of the closed end 120 from moving unduly so as to make noise.

Plastic bags (and sheet materials, generally) are notorious for the noise they can generate when being moved about. The tension force provided by the elastic strips 140, 150 serves to mitigate this noise by minimizing how much the flow stop moves when fluid pressure is applied across its closed end 120 while stopping airflow. Although the flow stop is meant to be installed in rooms that are not being used, noise generated by a moving bag is not isolated to that room because the sound is conveyed efficiently through the ductwork into other, occupied rooms. Applying tension force across the closed end 120 effectively suppresses this noise.

The flow stop is useful in sealing a typical ventilation register in a central air system. The first embodiment flow stop according to FIG. 1 is shown in FIG. 2 being mounted to the diffuser 210 of a floor register 200 (shown in phantom). The flow stop 100 is hidden from view when the register 200 is reinstalled on its ventilation duct 220 (shown in phantom). The flow stop 100, in the form of an impermeable, elasticized bag, is fitted over the register's diffuser structure 210 and is held in place by its peripheral elastic band 130 formed about the peripheral edge 124 of the open end 122 of the body 110. The elastic strips 140, 150, which are affixed across the closed end 120 of the body, apply tension forces across the closed end 120. The tension structure made up of these elastic strips 140, 150 allows the flow stop to expand and contract to fit registers of varying sizes and shapes, while applying a tension force across the closed end 120.

According to an exemplary embodiment, the elastic band 130 is about 3 inches wide, and the elastic strips 140, 150 are 2 to 3 inches wide. The substantial width of the elastic band 130 provides reinforcement around sharp edges of the diffuser. The substantial width of the elastic strips 140, 150 helps the flow stop accommodate larger range of ventilation register sizes, and approach the ideal where one size of flow stop fits all sizes of ventilation registers.

Referring to FIG. 3, the flow stop 100 is shown in a cross section view along the section line indicated FIG. 1. The elastic band 130 is disposed on the outside of the body 110 at the peripheral edge 124 of the open top end 122. The elastic strips 140, 150 extend along the inside of the closed bottom end 120 and up along the inside surface of the side 114. In addition to noise suppression, the elastic strips 140, 150 provide an added advantage of helping the flow stop to fit securely on ventilation registers of varying sizes.

To show the relationship of the elastic strips 140, 150 to the elastic band 130, FIG. 4 shows a detail view of one end 144 of an elastic strip 140 near the peripheral edge 124 on side 114. The elastic strip extends to be at or near the peripheral edge 124, and is disposed so as to overlap a portion of the side 114 over which the elastic band 130 (indicated by phantom lines in this view) is disposed.

This construction is appropriate for affixing the elastic materials to the body via heat or adhesive bonding or sewing. Many manufacturing processes are suitable to adhere the fabric to the elastic on a fixture that stretches out the elastic elements to substantially their fullest extent, so that when released from the fixture the flow stop will have sufficient elasticity to be placed around diffusers ranging in size from as small as 8 in.×4 in. to as large as 16 in.×8 in.

According to an alternate embodiment, refer to FIG. 5, which shows a detail view of one 144′ end of an elastic strip 140′ near the peripheral edge 124 on one side 114. For this alternate embodiment the end 144′ of elastic strip 140′ extends to be near the peripheral edge 124, however it does not overlap that portion of the side 114 over which the elastic band 130 (indicated by phantom lines in this view) lies. This construction is appropriate for mechanical fastening or adhesive bonding or sewing of the elastic materials to the body.

FIG. 6 shows a perspective view of a flow stop according to another alternate embodiment. The flow stop 600 has a body 110 with sides, top, and bottom that are analogous to those illustrated and described above with respect to FIG. 1. Plural elastic segments 632, 634 are disposed about the top edges of the four sides 112, 114, 116, 118 that make up the peripheral edge 124 of the open top end 122. The elongated elastic segments 632, 634 together provide spring forces that hold the body 110 of the flow stop 600 in place on a ventilation register.

A pair of elastic strips 640, 650 are each disposed across the closed bottom end 120. The elastic strips 640, 650 apply tension force across at least a portion of the closed end 120. The tension force applied to the closed end 120 by the elastic strips 640, 650 serves to prevent any excess material of the closed end 120 from moving unduly so as to make noise.

As shown in FIG. 6, the elastic segments 632, 634 are relatively narrower than the elastic band 130 shown in FIG. 1. Also, the elastic strips 640, 650 are shown in FIG. 6 as being relatively narrower than the elastic strips 140, 150 shown in FIG. 1. This diversity of illustration of these elastic members indicates that, although substantial width of the elastic band 130 and the elastic strips 140, 150 of the illustrated embodiment of FIG. 1 are regarded as having useful advantages, these substantial widths are not necessary to practice the invention. Embodiments using relatively narrower elastic members (as shown in FIG. 6) are regarded as falling within the scope of the invention, provided that elastic material used has a sufficient modulus of elasticity to hold the flow stop in place on a ventilation register.

In the above embodiments the elastic about the circumference is described and shown as being on an opposed face of the sheet from where the laterally disposed elastic members. This placement on opposed faces is not critical to the practice of the invention, which may alternatively be embodied to have all elastic components disposed on a single side of the impermeable sheet.

A flow stop bag is advantageously formed of materials impervious to air. Polymers are a class of materials that typically block airflow well. For example, nylon film (commonly used to make consumer-grade balloons) and polyethylene film (commonly used to make grocery bags) are both strong, inexpensive, and airtight. Other polymers may be suitable for the flow stop, depending upon burst strength and impermeability. Although flash spun polypropylene sheets (sold under the name Tyvek®) have excellent resistance to tearing, they are breathable and, thus, should be combined with a second film, such as a polymer coating or metallic film to make the sheets impermeable to air.

Embodiments of a flow stop for blocking flow of air through a ventilation register have been described. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the scope of the invention disclosed and that the examples and embodiments described herein are in all respects illustrative and not restrictive. Those skilled in the art of the present invention will recognize that other embodiments using the concepts described herein are also possible. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an,” or “the” is not to be construed as limiting the element to the singular. 

1. A flow control device for use with a ventilation register comprising: a sheet of material that is substantially impermeable to passage of air, and that is formed so as to have a first, closed end and a second, open end; a peripheral tension structure connected about a peripheral edge of the open end and sized to provide a gripping fit of the open end about a portion of the ventilation register; and a motion control tension structure connected to the closed end to apply tension force across the sheet.
 2. The flow control device of claim 1, wherein the portion of the ventilation register is a diffuser, the open end being sized to fit about the diffuser and the peripheral tension structure being sized to provide a gripping fit of the open end about the diffuser.
 3. The flow control device of claim 1, wherein the peripheral tension structure comprises one or more elastic bands.
 4. The flow control device of claim 1, wherein the peripheral tension structure comprises one or more pieces of elastic material.
 5. The flow control device of claim 1, wherein the motion control tension structure comprises one or more pieces of elastic material.
 6. The flow control device of claim 1, wherein the motion control tension structure comprises two or more pieces of elongated elastic material oriented substantially parallel to one another.
 7. The flow control device of claim 1, wherein the motion control tension structure comprises at least one piece of elongated elastic material disposed across the closed end and having opposed ends attached adjacent to the peripheral tension structure.
 8. A flow control device for use with a ventilation register comprising: a bag having a first, closed end and a second, open end, the bag being formed of material that is substantially impermeable to passage of air; a peripheral tension structure connected about a peripheral edge of the open end and sized to provide a gripping fit of the open end about a portion of the ventilation register; and a motion control tension structure connected to the closed end to apply tension force across the sheet.
 9. The flow control device of claim 8, wherein the portion of the air register is a diffuser, the open end being sized to fit about the diffuser and the peripheral tension structure being sized to provide a gripping fit of the open end about the diffuser.
 10. The flow control device of claim 8, wherein the peripheral tension structure comprises one or more elastic bands.
 11. The flow control device of claim 8, wherein the peripheral tension structure comprises one or more pieces of elastic material.
 12. The flow control device of claim 8, wherein the motion control tension structure comprises at least one piece of elongated elastic material disposed across the closed end and having opposed ends attached adjacent to the peripheral tension structure.
 13. A flow control device for use with a ventilation register comprising: a bag having a first, closed end and a second, open end, the bag being formed of material that is substantially impermeable to passage of air; a peripheral tension structure connected about a peripheral edge of the open end and sized to provide a gripping fit of the open end about a portion of the air register, the peripheral tension structure comprising one or more elastic bands; and a motion control tension structure connected to the closed end to apply tension force across the sheet, the motion control tension structure comprising at least one piece of elongated elastic material disposed across the closed end and having opposed ends attached adjacent to the peripheral tension structure.
 14. The flow control device of claim 13, wherein the portion of the air register is a diffuser, the open end being sized to fit about the diffuser and the peripheral tension structure being sized to provide a gripping fit of the open end about the diffuser.
 15. The flow control device of claim 13, wherein the material comprises a polymer sheet.
 16. The flow control device of claim 13, wherein the material comprises a nonwoven fabric.
 17. A flow control device for use in combination with a ventilation register having a face plate with a vent and skirt extending outwardly from the face plate for insertion into a forced air duct outlet, the flow control device for disposition about the skirt for blockage of air flow from the duct outlet, wherein the flow control device comprises: an impermeable and pliable sheet material, a clamp structure secured along the periphery of the sheet material to secure the sheet material to the skirt, and a noise suppression member secured laterally across the sheet material to apply tension force to the sheet material.
 18. The flow control device of claim 17, wherein the clamp structure comprises one or more elastic bands.
 19. The flow control device of claim 17, wherein the noise suppression member comprises one or more pieces of elastic material.
 20. The flow control device of claim 17, wherein the noise suppression member comprises at least one piece of elongated elastic material disposed across the closed end and having opposed ends attached adjacent to the clamp structure. 